How can I remove dry paint from door hinges?

One of the easiest ways is to take the hinges off the door and put in an old or thrift shop pot (you won't want to use the pot for food again) on the stove with water and baking soda... brings to a low boil and simmer for at least an out..... the expansion of the metal in the hot water makes the paint pop right off.... a little scrubbing with a wire brush and you are done

https://www.youtube.com/watch?v=R6pyxZKiZdQ

I use the crockpot method but here are 4 different ways.

https://www.prettyhandygirl.com/4-ways-to-remove-paint-from-metal-hinges/

Various options. If it's latex paint soak overnight in water and then use a scrubbie on them. If that doesn't work simmer them in a crock pot or pot to soften. If it's oil based try soaking in oil over night then use a plastic scraper. Or try a heat gun and scraper. I've had to use sand paper when there was also rust present.

Put them in an old can. Por boiling water and baking soda over them. The paint will peel off.